I would like to back-up IO540's posting and add that the pilot is very lucky that they have not been charged with manslaughter........do similar in your car or on the railway and you will!
"Inadvertent" entry into cloud is practically total bo11ox. Considering modern met data availability and the mobile telephone etc etc not to mention those nice big windows fitted to the aircraft.
You see a cloud, you decide if you want to fly into it or not.
OK the only alternative may be a precautionary landing but the fact is that forced landings poorly executed under control are far more surviveable than CFIT.
The departure climb must end at an altitude that provides 1000ft separation vertically from terrain within whatever navigational accuracy each side of track you can manage and this must be maintained as well as full VMC during the flight. The only exceptions being clearances in controlled airspace and low level corridors where operation at minimum level can be normal.
If you can not maintain 1000ft above terrain within Xnm each side of track then you divert.
Sods law says that during the diversion the weather gets worse so you may end up being forced to operate a level between the 1000ft minium and a 500ft minimum level.
If that is hard then simply a precautionary landing with power is the safer option.
Basic training!
I remember a rather heated debate some time back about turn back in a valley or go IMC or make a precautionary landing. Perhaps this pilot did not read that debate.
Having operated from Mona before, I can say that everyone with a map in that area recognises the coastal route to the river Dee.
Regards,
DFC